Ments



May 10, 1932. A. G. KKNYON CONVEYING SYSTEM Filed March 8, 1924 4Sheets-Sheet 1 KHATTORNEY5 May 10, 1932. A G. KINYON CONVEYING SYSTEMFiled March 8, 1924 4- Sheets-Sheet a INVENTOR 29 fli 10M fl {ATTORNEYSMay 10, 1932 A. G. KINYON 3 9 CONVEYING SYSTEM File March 1924 4Sheets-Sheet 4 INV N OR h ,XQATTORNEXQ ALONZO e. xmYoN', or

- quantitv of material which is to be of this invention is particularlyadapted Patented May 10,1932

UNITED STATES PATENT OFFICE ALLENTOWN, PENNSYLVANIA, ASBIGNOB, BY HESHEASSIGN- KENTS, TO THE ESTATE OF JAMES W. FULLER, DECEASED, 0FCATASA'UQUA, 2mmsYLvaN'IA Application and limb a, 1924. Serial Io.897,728.

- This invention relates to conveying systems and more particularly to asystem which is intended to be used for the conveying and distributionof material in a finely divided state. It offers numerous peculiaradvantages in connection with the handling of pulverulent material whichis stored at a central point and then distributed to various remotepoints to be used; for instance, the systpm or use in the handling ofpulverized fuel. The details of the invention will therefore bedescribed in that adaptation although it is to be understood that theutility of the principles of the invention is not limited to anyparticular pulverulent material and the use of the term pulverized fuelis intended to include other similar materials which may be handled bythis system with equal facility. It is customary in connection with theuse of pulverized fuel to carry on the grinding and pulverizingoperations in some central location, from which the pulverized materialis distributed either directly from the pulverizers, weigh bins orstorage bins, to the bins from which the material is conveyed to theburners. Frequently the latter bins are located at points which arespaced apart considerable distances and it is therefore desirable toprovide a system of conveying the material to these bins by which theoperator, stationed at the central station, may control the distributionof the material to the bins where it is required, and may also beadvised by suitable indicating devices as to the condition of such binsat all times. The present invention is intended to provide such a systemand it involves the use of a pump or other similar device which propelsthe material through a system of transport lines which are of a sizeappropriate to ghe 1stributed. These lines extend to the several bins inwhich the material is to be deposited and each bin is connected with themain line. Located at each bin is a valve arranged so that the operatormay shut off the flow of material beyond this bin and cause the entireflow to pass into the bin. These valves are operated by mechanism underthe control 'the next bin in the series.

of the 0 erator and devices located at the operators station indicatethe positions of the several valves. At each bin devices are providedwhich are brought into action when the material level in the bin reachescertain redetermined points and these devices cause Indicators at thecentral station to give a signal. Each bin may have a device to show theoperator when it is full, and another device which shows when thecontents of the bin has reached a certain low level. Also, the device ineach of the bins except the last brought into action when the materialhas reached the high level operates to close the valve so that when thelevel of the material in that bin has brought the device into operation,the valve for that bin is closed and the material then flows along themain line to The last bin in the series; that is, the one which is lastfilled under normal conditions, is provided with two such devices, oneof which operates when the bin is nearly full to actuate a warningsignal, preferably audible, calling the opertors attention to thecondition of the bin. Should the operator, for any reason, however, failto observe this signal, then, when the material has reached a stillhigher level, a second device is brought into action which shuts downthe pump so as to stop the flow of material in the system.

As will be seen from the brief description of the invention above setforth, it involves the provision of transport lines by which material isdistributed from a central location to a series of bins,-means forpropelling the material through these lines, means by which the flow ofmaterial to each of these bins is manually controlled, meansautomatically operating when the material has reached a certain level inthe bin for shutting off the flow of material to that particular bin andcausing the material to pass beyond to the next bin in the group, andmeans in the last bin of the series by which the entire system may beautomatically shut down whenever the material in that bin reaches apredetermined height. The invention also involves the provision ofimproved remotely controlled valves, preferablyelectro-pneumatitransport line is an air line cally operated, devices inthe bins which cause the valves to be closed when the level of thematerial in the bin reaches certain predeterm-ined points, and variousother elements and combinations of elements which will presentlv be setforth in detail.

I One embodiment of the invention is lllllS- trated in the accompanyingdrawings, in connection with the conveying and distribution ofpulverized fuel, and in these drawings,

Fig. 1 is a diagrammatic layout of such a conveying system in which fivebins are used, three located 011 the main line, with two located on abranch line,

Fig. 2 is a view in side elevation of the electro-pneumatically operatedtwo-way valve for controlling the flow of material from the transportline to the bin,

Fig. 3 is a sectional view of this valve on the line 33 of Fig. 2,

ig. 4 is an end view partially in section, on the line 44 of Fig. 2,

Fig. 5 is a top plan view of the devices shown in Fig. 4, illustrated inthe piping connections.

Fig. 6 is a sectional view of a detail of the air connection for thevalve,

Fig. 7 is a longitudinal, sectional view of one of the devices by whichthe indicators are actuated,

Fig. 8 is a cross-sectional view of the same,

Fig. 9 is a diagram of electrical circuits which may be employed in thesystem shown in Fig. 1,

Fig. 10 is a detail of a modified form of switch which may be used withthe mechanism shown in Fig. 7, and

Fig. 11 is a diagrammatic view of a switchboard showing indicating lampsand control buttons.

Referring now to these drawings, and particularly to Fig. 1, the systemis shown to include a main transport line 10 along which three bins arelocated, and a branch line 11, on which two bins are located. Thematerial is forced into the linelO by means of a pump 12 of the screwconveyor type directly connected with a motor or other source of power13. The intake 14 of the pump is connected with a storage bin or weighbin, or may receive the material directly from the pulverizer,'as may bedesired. Associated with the 15 connected with an air reservoir or othersource of supply. In this air line are suitable gauges 16, located atthe operators station near the pump, and also various branch connectionsand control valves therefor, by which air is led to the pump. Thepump-which I prefer to use in this connection is that illustrated in mycopending application, Ser. No. 329,209, filed October 8, 1919, Patent N0. 1,553,539, September 15, 1925, in which the pulverized material ismixed with air under such conditions that it takes on the mobility of aliquid andmay conse uently be readily conveyed to considerable istanceswithout great expenditures of power. The main air line beyond the gaugesand the pump connections extends alon r the transport line and is usedto actuate tie electro-pneu'matic mechanism which operates the valves.

In the system illustrated which is s mply representative of one layout,a branch line 11 is connected to the main transport line 10 through anelectro-pncumatically operated valve 17, and in this branch line are twobins 18 and 19. The bin 19 is connected with the branch line through avalve 20 similar to the valve 17, while the bin 18 is directly connectedwith the end of the branch line Without the interposition of a valve.The bins may be of any desired form having closed tops 21 provided withvent stacks 22. On the top of each bin is located the mechanism by whichthe signals at the central station are brought into action when thelevel of the material in the bin has reached a predetermined point.Beyond the valve 17 the main line continues for the purpose of supplyingbins 23, 24, and 25. The bin 23 is supplied through a branch 26, whichconnects with the main line through a valve 27, and the bin 24 issupplied through a branch 28 connected to the main line through a valve29. The bin which is the :last bin of the series, is directly connectedto the end of the transport line. In addition to the control valves bywhich the material is diverted into the bins, the main line is providedwith blow-out valves 30 at different points along its length, theseblow-out valves being connected with the main air line through suitablebranch connections having control valves therein.

The two way valves 17, 20, 27, and 29, by which the branch lines leadingto the bins are controlled are illustrated in Figs. 2, 3, 4, and 5. Eachvalve consists of a main body portion 31 having a flange 32 at one end,provided with the flange 33 on the transport line, a union by which thevalve is connected in the line. The main body portion 31 is hollow andhas an enlarged end 34 forming a housing 35 in which the valve disc isto operate. Associated with the valve body is a valve discharge branchwhich carries at one end a plate 36 which is a'dapted to be secured to aperipheral flange 37 located on the rim of the casing 35 by bolts 38.Extending from the plate 36 is a 39 which provides a continuation of themain line, being connected to this line by means of a ange union 40.Also extending from the plate 36 is a pipe or elbow 41 which isconnected with the branch line by a flange union 42. The ports through43 located within the housing 35. ThlS (1150 18 carried on the end of anarm I pipes.

various parts are in their shown to the left in 44 which is, in turn,mounted on ashaft 45 which is supported in a bearing 46 forming a partof the plate 36. A gland 47 is also provided in connection with thisbearing and the shaft 45 has longitudinal and circumferential groovesfor a lubricant which is supplied thereto by means of a grease cup 48.Extending through the wall of the housing op- )osite the end of thevalve disc arm shaft 45 IS an adjusting bolt 49 by which the position ofthe shaft and the bearing of the disc against its seat may be adjusted.On the outer end of the shaft 45 is a crank 56 which is connected by alink 51 to anothercrank 52, mounted on a shaft 53. The shaft is mountedin a framework 54 secured to the pad on the upper surface of the mainline pipe its length may be varied as desired, and the crank 52 isprovided with a plurality of apertures in its outer end so that thepoint of connect-ion ofthe crank and link may be varied. "his permits ofvarying the throw of the valve disc so that this throw may be given theproper length according to the size of the orifices of the main line andbranch line The shaft 45 may be placed in either side of the valve,according to local conditions. Also the crank 52 is ada ted to projectfrom either side of the sha t 53 so that connection thereto can be madeto crank 50 at either side of the valve. 1

Secured to the upper end of the framework 54 are cylinders 56, as shownin Fig. 4, in each If which moves a piston 57 Each piston has a rackinstead of a piston rod, which rack engages theteeth of a pinion 58mounted on the shaft 53. With this arrangement when one piston is forceddownwardly by compressed air the other one is raised so as to be inopgrative position. In Figs. 2 and 4 the proper relation to permit thepulverized material to flow from the main transport line into thebranch. Accordingly, the disc 43 is in its uppermost position and theappropriate piston is raised so that when air is admitted to thecylinder Fig. 4, the valve disc will be moved downwardly to close thebranch line connection andpernnt the material to flow on through themain line.

Air isadmitted to the cylinders 56 from the main air line 15 through abranch connection 59 is which is an air strainer 60, together with acut-out valve 61. As shown in Fig. 5, the branch air line 59 terminatesin lateral branches 62. each of which supplies air toone cylinder of thematerial valve operating mechanism. and also permits the escape )f airfrom this cylinder. One of these valves is illustrated in Fig. 6, andlocated in the body of the valve is a small pin valve 63 which islocated directly beneath the core 64 of a solenoid 65. The branch airline 62 connects with a passage through the body of 39. The link 51 isso constructed that the valve which is normally closed by the pin valvebeing forced against its seat by a spring 66, the passage extendingbeyond the pin valve into the u per part of the cylinder. When thesolenoid 65 is energized its core moves downwardly and unseats the invalve thus permitting air to be introduce into the cylinder and socausing the valve disc 43 to be moved from one port to the other. Inorder that this movement may be complete the operator must depress aswitch button on a control board and keep the button depressed untilsuch time as the piston has moved to the end of its path of travel. Whenthe button is released and the solenoid de-energized, the spring 66together with the air pressure forces the spring valve 63 against itsseat while the air within the cylinder returns through the passage 67and escapes through the port 67 to the atmosphere. The plug 64' closesthe aperture necessarily made in drilling the aperture 67 The piston,however, remains in its lowermost position until the piston in the othercylinder is operated. A similar action of corresponding parts of thesolenoid 65 and pin valve on the other cylinder occurs when the devicebrought into action when the level of the material reaches apredetermined point closes the circuit to the other solenoid, closingthe valve to the bin as explained more fully hereinafter.

In order to indicate at the central station when the piston has moved toits limit of travel, thus indicating that the valve disc has moved toclose the desired port, there may be employed electric indicating lampsin a circuit which is controlled by a switch 68 mounted on the crank 50and consisting of a casing within which is a quantity of mercury 69.Disposed above the mercury is a terminal member 70 from which dependthree contact points, one of which is designated by the numeral 7-1.These contact members are arranged so that when the switch is moved tothe right or left the mercury establishes a contact between the centralpoint and one or the other of the outer points. Appropriate circuits arethus established through the mer cury to light lamps at the centralstation, one of which indicates the 0 en, the other the closed positionof the va ve. Consequently in operating the valve from the centralstation the operator will close the circuit which actuates theappropriate pin valve, thus causing air to be introduced into the propercylinder. This circuit will be kept closed until such time as one or theother of the circuits through the contacts and the mercury has beenclosed. whereupon the lamp will indicate that the valve disc has movedto the des red position. The switch casing 68 is mounted in a clamp 72,secured on the crank 50 and provided with a plurality ofjaws. each ofwhich has set screws and jam nuts so that the casing is not only firmlyheld in position,

but may also be given the desired exact adustment necessary to cause theindicating ward station.

. controlling the flow tion that it .to be shut down.

which operate when the material has reached certain level in the bin.

As previously mentioned, each of the bins contains a device brought intoaction when the level of the material reaches a predetermined pointwhich operates, in the case of each bin except the last, to cause thevalve of material from the main line into that bin to be closed when a.

redetermined level has been reached. In the ast bin of the series thereare provided two such devices, one of which causes a preliminary warningsignal to be operated and the other of which causes the pump mechanismIn addition to the devices a predetermined level, the bins may also havedevices which cause signals to be given, showing when the material hasfallen below a In each case the mechanical construction of the mechanismis substantially the same, the connections with the signals. beingvaried to produce the desired results.

Each device consists of a pendulum 74 which is suspended from the top ofthe bin and which carries a paddle 75 at its lower end. This paddle ismounted in such a locais moved from its vertical positionby the flow ofmaterial over the top of the pile in the bin as the latter is beingfilled. The pendulum 74 extends upwardly through a slot- 7 6 in the topof the bin and a registering slot formed in the base 77. A canvas sleeve78 is secured to the pendulum and to the base around the slot so thatthe entrance of dust from the bin into the casing may be prm'ented. Thependulum is pivoted between hardened steel points 79 formed on the endof threaded members which are secured in suitable lugs 80, thesethreaded members being capable of adjustment as may be desire and beingheld in adjusted position by suitable jam nuts. The upper end of thependulum which is flattened in order that it may project through theslot and also provide a suitable bearing surface for the points, isconnected by suitable links -81. 81, which are, in turn, connected by aarm of a bell crank 83 pivotally mounted in a lug 84 extending upwardlyfrom the base of the device for use in connection with electric signals.The other arm 85 of this bell crank carries a mercury switch whichconsists of a sealed glass tube turn buckle 82 to one the connectionspreviously to close the 86 having a quantity of mercury 87 within it.Sealed in the opposite ends of the tube are contacts 88 which are soarranged that when the tube is to lie either in one end or the other, acircuit will be closed between the adjacent contacts and the mercury.The contacts atone end of the tube are properly connected witha suitablelamp at the switchboard, and the contacts at the other end of the tubefunction circuit to the solenoids which operate to close the valve tothe bin, so that as the material piles bell crank to tilt so that to oneend or the other The entire operating mechanism is enclosed with- 1nacover 89 so as to protect it from dust.

The device just described maybe used for indicating either the high orlow level of the material in the bin by a suitable arran ement of theelectrical circuits. Also, in which is the last bin of the series, thereare provided two highlevel indicating devices, one of which has apendulum somewhat longer than the other. has the longer pendulum isarranged'to establish a circuit which operates a warning si nal at theboard. preferably anaudible signal, such as an electric horn or bell,and is intended to attract tilted to permit the mercury Thedevice 90which This warning signal isup in the bin the pendu lum 74 will be swungout of the vertical and the'operators attention to the-condition of beenfound thatthe device which indicates 1 under certain condithe low levelis likely, tions, to give a wrong indication unless provision is made topermit the endulum to swing in both directions away cal axis. This isdue to a tendency of the puls verized material to rathole directly overthe point where it is being withdrawn at the bottom of thebinand as fillup the rathole. Sometimes as a result of these slides the signalpendulumvis carried back to its verticalposition, although when thesliding material has reached a condition of repose its level may beconsiderably above that of the paddle. This would cause the signal togive the wrong indication. This difliculty, however, has been overcomeby slight modifications in the construction of the de-.

vice. For this purpose the base of the device is cut away slightly as at92 so as to permit the pendulum arm to move to either side of itsvertical position, and the mercury switch rom a .verti- 11: the materialconi I tlnuesto feed out of the bin slides occur which i ciao ' A switchgenus is given the modified form illustrated in Fig. 10. In this figureit will be noted that the glass tube 93 has a depression 94 mid-way ofits ends and the contact members 95 sealed through the tube are solocated that when the tube is exactly in its horizontal position themercury will lie in the depression and will electrically connect bothcontacts. However, if the tube is tilted slightly one way or the otherthe mercury will travel to the lower end of the tube and but a sli htmovement is necessary in order to throw t e mercury away from thecontacts and thus break the circuit. These contacts are connected with alamp at the central station so that when the tube is in horizontalposition the lamp is lighted, thus indicating that the material is at orbelow the height of the paddle associated with this indicator. When thetube is moved to either side of its horizontal position, the lamp goesout and in the case of a slide the pendulum will ordinarily move from aninclined position at one side of the vertical, to an inclined positionon the other side. In this case the lamp at the central station wouldsimply make a flash, but would not continue lighted unless the pendulumcame to rest exactly vertical. The probabilities of this occurring upona slide taking place are so slight that the signal has been found towork satisfactorily under normal pperating conditions. In Fig. 9 thereis shown a switch board 96 used in connection with an electric signalingsystem, this switch board being located at the central station where theoperator stands. In this diagram there are shown the connections fromthe central station to the actuating device in two of the bins, onebeing an intermediate bin, while the other is the last bin in the line.It will be understood that when additional intermediate bins areemployed, similar circuits to those which will presentlybe described aremade use of. board of a form appropriate for the system illustrated inFig. 1 is shown in Fig. 11. The first lamp 97. at the left of the switchboard is in a circuit which is controlled by mechanism actuated when thematerial in the intermediate bin reaches a certain predetermined highlevel. Next to this lamp is a lamp 98 which is lighted when the 'alveassociated with the bin is in the open position. Next to the lamp 98 aretwo buttons designated as open and closed, one of which, when depressed,establishes the circuit opening the valve, the other the circuit bymeans of which the valve is closed. Beyond the buttons designated openand closed is a lamp 99 which is lighted when the valve is in the closedposition. Beyond the lamp 99 is another lamp 100 which is lightedwhenever the material 1n the blXl has fallen below the level of the lowlevel paddle. Beneath the lamps and buttons just described is a lamp 123connected in a circuit controlled by a device in the last bin, thislampv being lighted when the material in that bin reaches apredetermined high level. Also the board contains a lamp 124, controlledby a device in the last bin, and lighted when the material.

in the bin reaches a certain predetermined low level. Diagramniaticallyindicated at 125- is an audible signal which is in a circuit actuated bya control device in the last bin.

Mounted on the board are bus-bars indicated by the lines 101 and 102,which are in turn connected to a source of current at a suitablevoltage. The entire system is controlled by a main switch 103 locatedbetween the busbars and the line.

In the circuits illustrated the valve for controlling the material flowis in the closed position while the actuating device is in that positionwhich it would assume when the material is below the level of thepaddle. It will now be seen that there is a circuit through the lamp 97as follows: Through the line 104, contacts 88', mercury 87, the contactsand mercury being located on the arm associated with the bin signal,thence through the return line 107 to the bus-bar 102. The lamp 97 islighted, indicating that the material has fallen below the level of theendulum. Since the valve controlling the ow to that bin is closed, thelamp 98 is out, while the lamp 99 which indicates that the valve is inthe closed position, is lightedj The circuit through the lamp 99 is asfollows: from the bus-bar 101 through the line 108, to the contact 109,mercury 69, central contact 111, thence to the return line 107. \Vhenthe operator depresses the switch button marked Open, this establishes acircuit through the line 112, solenoid 65, and to the current resistor114, and return line 107. So long as the switch button Open is depressedcurrent will flow through the circuit just described, and when theadmission of air to the cylinder associated with the solenoid has forcedthe piston within that cylinder to its lower limit of travel, the switch68 will have tilted to the opposite inclined position, whereupon themercury will break the circuit through the lamp 99 and establish acircuit through the lamp 98 by contacting with the points 111 and 71.This circuit through the lam 98 is as followszfrom bus-bar 101 througiithe line 108', through contact points 71 and 111 to the return line 107.

When suflicient material has been discharged into the bin to cause thehigh level indicating device to swing, the switch 86 will have taken theopposite inclined position so that the mercury 87 closes the contacts88. This establishes a circuit as follows: from the bus-bar 101 throughline 119 across cons tacts 88, through mercury 87, thence through theline 120 and through the solenoid 65' and current resistor 114 to thereturn line 107.

Uponthe establishment of this circuit by the ,bar 101 through lam theline 123, throug inter the material in the last bin reachesa'certainpredetermined. lower. limit, an indication is givenat the, maincontrol station. When the,

reaches a certain hi is o erated, and w 1 a still higher level the motorwhich drives the pump propellin the material through tilting of theswitch 86 the solenoid is.

energized, admits air into the cylinder which causes the valveto'close'and no further material is then discharged into thev bin; The

low level 'indicatingldevice in the bin is provided with a switc 122actuated by means of a pendulum and paddle-as previously de- I scribed."Whenthe v er levelthe switch will beplaced in such position that} themercury closes the circuit through its contacts, whereupon a circuitwill7 material reaches the lowbe establishedjas follows: from the main bus100,- thence throu the contacts in t switch '122 to the return line 107.

'-:-,The last bin in the series is directly connected to the transportline, and no valve is osed in the connection. This bin is rovide with adevice having a pendulum which extends down into thebin to a point nearthe bottom thereof. This endulum is of the con-' struction previouslyescribed, and actuates .pendul um in this bin carries a switch 129,

-' provided with mercury 130, and pairs of con-' tacts 131 and 132mounted in the ends of the tube in which the mercury is contained. .A

third pendulum mounted in this bin carries .a switch 133, provided witha pair of con-' tacts 134 in one end of the switch tube which.

also contains a quantity of mercur 135. e

It will be recalled .that'when t e level of velfof the material beingfed to this bin h level an audible signal en the material reaches thesystem is stoppe The circuits by which these results are brou ht aboutelectrically: are as follows: When t e material in the bin reaches thelow level, the switch 128 is in the position shown in the drawings, atwhich time a circuit is established as .follows: from the bus-bar 101which leads from the main busbar 101 to the switch 103, through the lamp124, line 136, one of the terminals 127, through the mercury 128, andthe other terminal 127 to the return line 137. The lamp being lightedshows the operator that a sufficient quantity of material is not presentin the bin, and he may close the valves in the system so that thetransport line will deliver into this bin. In the illustration, theswitch 126 is in-the osition that it would occupy .while thebin s beingfilled.

60 1 1 erates in one position. to maintain a lamp The switch 129 shownin the drawings, op-

lighted at" the central station, when the material in the bin is belowthe level of the pendulum by which the switch is operated. When theswitch is in the position shown,

the lamp 123is in a circuit as follows: From bus-bar 101' to lamp 123,line 138, to one of the contacts 132, through the mercury 130 totheother contact 132, and back to the return line 137. When the materialentering the bin reaches a level suchthat the pendulum is swung and theswitch 129 is tilted, the mere runs'awa from the contacts 132, when t ecircuit a ove described is broken and the lamp goes out, thus visuallyindicating that the material has reached the level of the pendulum. Thisswitch 129 isprovided with an additional pair of contacts 131 e in theopposite end so that when the pendulum reac mercury signal nowoperatesto notify the attendant that'thematerial has reached a certain highlevel in the bin. Should the attendant fail to cut oil the flow ofmaterial to the bin, the

third pendulum in the bin is swung when the material reaches a somewhathigher level.

This pendulum carries a switch 133, with con- 'tacts ;134. "-As shown inthe drawings, the 1 is i-n the position that it would occu whenthematerial has reached the high level: andfthef switch -.is closed. Inthis position the switch jcloses a circuit only a part of whichis shown.The circuit leads, however, to the motor and contains mechanism of theusual type for stopping the motor, as, for instance, by'means of a relaywhich throws the main motor-switch.

It will be, seen that with the connections above described, thecondition of the valves is shown to the operator at all times, and he isalso informed as to the level of the material in the last bin. As soonas the material in any bin reaches either a high or a low level, a ampis lighted and continues lighted so long as the condition exists. Also,when the material reaches a high level in the intermediate bins, acircuit is established which causes the solenoid at that bin to operatethe valve to shut oil. the further flow of the material to the him Whenthe material reaches the low level in the bin the operator is warned ofthe condition by the lighting of a lampon the board. As to the last binin the line, the si al actuating devices show when the level 0 thematerial has fallen below a selected. lower limit, causing, a lamp atthe switch board to-be lighted. Also, when the material has reached apredetermined high level, an audible warning signal is first actuatedand if the condition is not corrected and more material is dischargedinto the bin, a third device is moved so as to close a circuit whichcauses the motor driving the pump to be shut down.

' It will be seen that with the system above described it is possiblefor a single attendant to operate the system and to control thecondition of the bins at all times. The control mechanism may be placedat any desired point in the plant and may be as near to or as remotefrom the bins themselves as the layout of the plant may require. Theattendant is promptly warned whenever the material in the bins fallsbelow a predetermined low level and, in the case of each bin except thelast, whenever the material being discharged into the bin reaches a highlevel the valve by which the flow of this material is controlled isautomatically shut ofi, thus requiring no attention on the part of theoperator. The supply of the material to the individual bins is underdirect control and the distributing valves may be actuated from theswitch panel Whenever desired. For instance, should the material in twoor more bins simultaneously reach the lower level, it would be desirableto permit a small supply to be introduced into one bin withoutcompletely filling the bin so that there would be no danger of thesupply in the other bin entirely failing. The operator may exercise suchcontrol by opening the appropriate valve and permitting a certainquantity of material to be discharged into the bin which would be lessthan enough to actuate the high level indicator. By vmeans of the switchwhich closes the valve he may voluntarily shut off this supply and causethe discharge to commence into another bin. In this way less than acapacity quantity may be discharged into a number of bins without thenecessity of waiting until one bin after another is filled.- At the sametime the position of the bin valves is always shown on the panel so thatthere is no likelihood of the operator becoming confused.

Furthermore, while the system has been shown as arranged fordistributing material to five bins, two of which are located on a branchline, it will be understood that it is applicable to any number of binsarranged in any desired manner. Also its use is not limited to thedistribution of pulverized fuel, since it will be clear that thecharacter of the material conveyed does not afi'ect the operation of theseveral devices of which the system is composed. The means by which thematerial is moved through the system has been referred to as comprisinga motor driven pump, preferably of the type illustrated in my co-pendingapplication previously referred to. As disclosed in that application,this pump is so arranged that air is injected into the material beingpropelled, the aeration being such as to permit the transportation ofthe material through extended lines. The use of a propelling pump inwhich the material is transported in an aerated condition also improvesthe action of the indicating devices, since the fluid mixture of air andthe pulverized fuel may be given an increased velocity. Also thetransportation in this condition improves the action of the indicatingmechanism since the material discharged in the bin flows laterally morereadily and this lateral movement actuates the signal pendulum withgreater certainty.

I claim:

A conveying system of the class described which comprises thecombination of a main transport line, means for propelling materialtherethrough, a plurality of bins located along the main line, branchconnections between each of the bins except the last and the main line,the last bin being directly connected to the main line, a two-way valvefor controlling each branch connection, the said valve being alternatelyoperable to open the branch and close the mainline beyond the branch,and to close the branch and open the main line beyond the branch, acentral control station, means remotel controlled at the central stationfor opening and closing said valves, means for indicating-the conditionof said valves, means associated with each bin except the last operablewhen the material in said bin has reached said predetermined high levelto actuate the operating means of the valve associated with said bin toclose the branch line feeding that bin, and means associated with thelast bin only and operable when the material in said bin has reachedsaid predetermined high level to shut down the propelling means.

In testimony whereof I aflix my signature.

ALONZO G. KINYON.

